Grog is, most simply, a mixture of water and rum, with more complicated versions adding spices, citrus fruits, or sugar. Grog dates from the mid-18th century, when it was introduced as a way of reducing drunkenness on ships in the British Royal Navy.
Historically, the problem of liquid on board ships during long trips has been a difficult one for sailors to deal with. Water tends to grow algae and other plant life, and beer tends to spoil on long journeys. As a result, when rum was introduced in the mid-17th century, it quickly became the drink of choice for navies throughout the world. The British Navy particularly depended on it, and after 1655, a daily ration of ½ pint of rum was given to sailors. Unfortunately, many sailors became intoxicated and unruly from drinking rum, a problem that was exacerbated by men saving up their daily rations until they had a significant quantity stored that they could drink all at once.
In 1756, an Admiral Vernon came up with the idea of diluting his men’s rum with water. This not only made it less alcoholic, but the water also made the rum susceptible to spoiling if sailors chose to save it. From 1756 until 1970, the British Royal Navy served a daily ration, or tot, of grog on board each ship at 11 a.m. Admiral Vernon, the inventor of this practice of diluting the rum, was known not only as a friend to the sailors, but also for the waterproof cloak he wore, which was made from grogam wool. This cloak earned him the nickname Old Grog, and after his invention of the new ration, the nickname was transferred to his creation.
In later years, citrus was added to the traditional Royal Navy grog in order to ward off scurvy among sailors. Since sailors on board Royal Navy vessels often had to go for many months without fresh fruits or vegetables, adding lemon or lime juice to their grog helped to keep their vitamin C intake at sufficient levels. Another take on grog, popular on board pirate vessels, was known as bumbo or bumboo. Since pirate vessels tended to stay out for shorter periods of time and they kept themselves better fed, the lime and lemon juice could be left out of their mixture. Instead, they added sugar, nutmeg, and occasionally cinnamon to help flavor the grog and make it more palatable.
